She calls him Chilorio Man, a nickname that translates roughly as "Pulled Pork Guy.''

He's from northern Mexico, and his flawless English has a Latin timbre. She grew up in Essex, and though she hasn't lived there for a half-century, her accent still says "England.'' The student's a burly, black-haired 6-foot man, and at 38 he's less than half the age — and twice the size — of his thin, gray-haired teacher. That 85-year-old woman describes herself as "5 foot 3 and shrinking.''

An unlikely pair. Yet they're bound, great friends who share an even greater passion: the authentic cuisine of Mexico. This week they come together again when Rene Valenzuela, owner and chef of El Taconazo restaurant in Seminole Heights, hosts Diana Kennedy, the famed cookbook author who's often referred to as the Julia Child of Mexican food, at a series of events in the Tampa Bay area.

Kennedy will give cooking classes and demonstrations, including one at El Taconazo on Friday, and host at least two book signings. (A cooking class at the Rolling Pin in Brandon is sold out.) And of course she'll be tasting his food and checking out his kitchen to see just what her star pupil has cooking.

Everyone, including Valenzuela, calls his restaurant the Taco Bus, harking back to when the previous owner, a cousin of his, served takeout there from a converted school bus. (The bus remains and takeout is still an option, but there's indoor and outdoor seating, too). This funky, welcoming and affordable taqueria at 913 E Hillsborough Ave. has a devoted and mixed following, drawing hordes of food-savvy Anglos as well as Mexican-Americans hungry for a taste of home.

Preserving and promoting that real thing has been Kennedy's mission for half a century. In 1957 she married New York Times correspondent Paul Kennedy. They moved to Mexico, and she began researching the traditional ingredients, recipes and methods of that country's varied regions. Starting with The Cuisines of Mexico in 1972, her cookbooks and teaching have done much to put Mexican food on the map and the table in the United States and beyond. Her latest cookbook, published last year, is The Art of Mexican Cooking (Clarkson Potter), a 500-page reissue of a 1989 classic.

She has roamed Mexico for all those years, talking, chopping chilies and crushing herbs with the mostly older women who keep these traditions alive. Her dedication has helped spread the taste of rajas con queso (roasted poblano peppers stuffed with white cheese, corn kernels and cream) from Mexico City and the country's center, kingfish ceviche from Guerrero in the southwest, and yes, chilorio from the northern state of Sinaloa.

Valenzuela has been a passionate cook since he was 7 or so, bugging his friends' mothers and the cocineras at his grandmother's house to teach him to make their salsas and simple taquitos with potato and chili pepper fillings. By 9 he was selling them out of a cooler at a farmers market in Sonora, and during his high school years he ran a taqueria in El Centrito, the Ybor City of Monterrey. He came to the United States in 1994 and moved to Tampa in 1996. Today Valenzuela lives in Plant City, where he and his wife, Lladira Wagner, also run and own another restaurant, Taqueria Monterrey Mexican Grill.

By 2007 his cousin, Roberto Morfin, was burnt out on the restaurant business, and Valenzuela borrowed money from family and friends to make the Bus his own. All along, he returned to Mexico once or twice a year for his "continuing education" with local chefs. He had been devouring Kennedy's books, and a few years back — neither of them can remember exactly when — he came to his first culinary "boot camp,'' as she calls them, intensive, days-long Mexican cooking seminars. This one was in her home kitchen in the southern state of Michoacán (she lives there and in Austin, Texas.)

"I heard there was this extremely enthusiastic young man attending,'' laughs Kennedy, "and that he was very tall and handsome. Then I met him and he rushed up to me, very expansive and effusive, and told me he loved my books, especially the chilorio recipe. 'I've made a lot of money from that,' he said, 'and I'm very grateful.' So that's when I started calling him Chilorio Man.''

The next morning someone called in sick, so she asked Valenzuela to be her helper for the rest of the course. "I'll need you here at 7 a.m.,'' she told him. He showed up at 6. Since then he's returned for more study with her, including an intensive course on tamales in San Miguel, Guanajuato.

"She cares so much about the same thing I care about,'' Valenzuela says. "That's the beautiful, delicious, wonderful, authentic food of my country. And I'm humbled and grateful to learn from the woman who's been the ambassador of that food to the entire world.''

Kennedy has a reputation for strictness, lightened with humor. She doesn't allow perfume or cologne in her classes, for example, and she discourages "chatter.'' When it comes to the food itself, she's an orthodox traditionalist.

Is her pupil ready for this ultimate test? A visit from la maestra?

Valenzuela's not at all worried. "We have a relationship based on trust and carino (affection),'' he says. "So I simply look forward with pride for her expert eyes to give me the right perspective to grow as a chef.''

Nor, says the teacher, should he be concerned. "I am not going there as a food critic or health inspector!'' Kennedy says. "Rene is my host and from all I hear Taco Bus is a wonderfully happy local spot to eat. I'll be happy to make suggestions if he asks, and I look forward to rolling up my sleeves and getting my hands dirty in the kitchen.''

When Kennedy tastes Valenzuela's chilorio this week, what will she be looking for? "The right balance of chilies around the meat, the kind of pork he uses, the texture . . .''

He's had plenty of practice making it: Chilorio has been a popular Monday special at the Bus almost since the beginning. Most customers take it wrapped in two small flour tortillas, with the pork drippings soaking into the soft wrap. The fat is important and not to be shied away from, Kennedy says; she might even add lard to some batches.

Done the Diana Kennedy/Taconazo way, served with steam coming off the brownish shredded meat and a squeeze of lime added, the chilorio is savory and fragrant, not spicy hot, but deeply flavorful. Valenzuela's pride in his teacher and his food is justified when he calls it "an explosion of unbelievable goodness.'' And he says, "I give the credit to her, mi maestra de cocina.

John Capouya is a professor of journalism and writing at University of Tampa and the author of "Gorgeous George," a biography of the flamboyant professional wrestler. He is a former editor for Newsweek and the New York Times.

.MODERATE

Chilorio (Chili-Seasoned Pork)

2 pounds pork shoulder, without bone but with some fat

2 teaspoons salt

8 ancho chilies, seeds and veins removed

1/3 cup mild vinegar; increase to ½ cup of liquid by adding water

8 garlic cloves, roughly chopped

1/8 teaspoon cumin seeds, crushed

¼ teaspoon dried Mexican oregano

Salt to taste

Lard or solid shortening such as Crisco as necessary

Cut the meat into 1-inch cubes and cook with salt as for Carnitas (see accompanying recipe). When the water has evaporated and the fat has rendered out of the meat but the meat has not browned — about 45 minutes — remove the meat from the dish and pound it in a molcajete (mortar) until it is in shreds, or shred it finely with two forks.

Meanwhile, prepare the sauce. Cover the chilies with hot water. Soak for 10 minutes and drain.

Put the diluted vinegar into the blender jar with the garlic and spices and blend as smooth as possible. Gradually add the chilies and blend after each addition. The sauce should be thick, like a paste. You will have to keep stopping the blender to release the blades. Only add more liquid if necessary to release the blades of the blender.

There should be about ¼ cup of fat in the dish in which the meat was cooked; if not, make up to that amount with lard. Add the meat and mix the chili sauce well into it. Cook over low heat for 15 to 20 minutes, or until the meat is well seasoned and the mixture rather dry, scraping the bottom of the dish to avoid sticking.

Cut the meat, with the fat, into strips about 2 by ¾ inches. Barely cover the meat with water in a heavy, wide pan. Add the salt and bring to a boil, uncovered. Lower the heat and let the meat continue cooking briskly until all the liquid has evaporated — by this time it should be cooked through but not falling apart.

Lower the heat a little and continue cooking the meat until all the fat has rendered out of it. Keep turning the meat until it is lightly browned all over. Total cooking time is about 1 hour and 10 minutes.